Network Slicing

Network Slicing

What Is Network Slicing?

Network slicing is a virtual networking technique that creates multiple logical networks on the same physical network infrastructure, providing flexibility in the allocation and use of network resources.
Network slicing involves creating slices in a network according to the various needs of different consumers and industries to meet their requirements for service latency, reliability, and capacity.

Network slicing is important in emerging telecommunication networks such as 5G because, unlike previous technologies, 5G architecture and specifications have the capabilities to implement and deploy independent virtual network slices in support of consumers' and enterprises' use cases. The full implementation of network slicing in 5G will benefit the industry by generating new revenue streams, reducing costs, and improving the quality of service and experience for customers.

Consumers and enterprises can trace the history of network slicing back to the 1980s when the concept of the "slice" in networking was introduced. The first kind of network slicing provided by overlay networks involved several types of network resources combined to form a virtual network upon a common physical infrastructure.

How Does Network Slicing Work?

5G network slicing architecture allows for independent and virtualized logical networks on the same physical infrastructure. Engineers deploy network slicing functionality across the radio access network RAN, core, and data networks (formerly known as access point networks (APNs) to support the subscriber experience.

Each slice acts as an isolated end-to-end network that engineers configure and design for custom results based on application requirements to support various network services such as devices, vehicles, and broadband, each having its slice configuration and performance reporting. Each slice may account for the following characteristics:

• Slice isolation: Because network slicing requires the implementation of many diverse types of services, and some services share resources with other virtual slices, the isolation of a slice helps to ensure the quality of service.
• Diversification: Network slices can share network resources (for example, compute, storage, or bandwidth) with other network services; configuration to do so must be applied from the onset.
• Deployment: Advanced resource management of network resources is available for network slicing configurations to ensure rapid assignment of shared functions.
• Advanced management: Slice capabilities must allow subscribers to use diverse network functionalities while negotiating for quality of service.

Network Functions and Architecture

The network characteristics listed below detail the basics that support "building blocks" for creating network slices. Engineers can implement slices to ensure behavioral or functional performance.

• A network slice could span across multiple parts of the network (for example, terminal, access network, core network, and transport network) and be deployed across multiple operators.

A network operator can deploy:

• A single slice that is associated with multiple verticals
• Multiple slices of diverse types that are associated with a business bundle

For example, in the diagram below, a vehicle may need to have functions for a high-bandwidth slice for infotainment as well as an ultra-reliable slice to automatically collect and transmit sensor data about the driving experience. The entire infrastructure of antennas and routers is part of the physical infrastructure that supports network slicing. Each slice runs on top of a shared infrastructure as a dedicated, isolated network with its settings. Engineers configure slices to connect to end devices for various 5G services (IoT, broadband, and low latency) that best suit their needs.

Based on 5G use cases, the following are some additional examples of how slices might work in practice:

• Enhanced mobile broadband (eMBB): A slice for general mobile internet use with high-speed data.
• Massive machine-type communication (mMTC): A slice for many IoT devices (such as sensors) that connect simultaneously but do not require high speed.
• Ultra-reliable low-latency communication (URLLC): A slice for critical applications, such as self-driving cars or remote surgery, that need extremely low latency and extremely high reliability.

The Role of Virtualization and Software-Defined Networking

Virtualization provides the abstraction of the underlying physical resources with a homogenous and unified approach. It also supports a scalable slice-deployment strategy that depends on network functions virtualization (NFV) and allows each slice to decouple from its network hardware. Orchestration is a process that enables the coordination of all different network resources that engage in the network slice lifecycle. In this case, software-defined networking (SDN) helps to enable flexible and dynamic slice configuration.

SDN and NFV are key concepts that support the implementation of network slicing in 5G networks.

Software-Defined Networking

SDN is the type of architecture that makes networks more efficient and easier to manage by controlling the flow of data through networks, making networks programmable. It establishes management of the network through software to control the data flow of traffic from physical devices such as routers and switches, allowing network administrators to modify and optimize network settings and automate network tasks from a single interface. This centralized control makes it easy to change network paths, improve performance, and adapt to new demands.

SDN helps businesses scale up or down based on their needs without the hassle of updating physical equipment. This flexibility is especially useful for large organizations such as cloud providers and for data centers that need to adapt quickly.

SDN reduces the reliance on hardware and can also lower costs over time because software-based management generally is more affordable and efficient than maintaining complex physical infrastructure.

Network Functions Virtualization

NFV is a way of using software to perform tasks that require specialized hardware. Traditionally, networks depend on dedicated hardware such as firewalls, load balancers, or routers for each specific function. With NFV, these functions are virtualized and run as software, which makes them much more flexible and cost-effective. For example, instead of setting up a physical firewall device, a network administrator can use a virtual firewall-software that does the same job but runs on general-purpose servers. Other examples include virtual routers and virtual load balancers, which help distribute network traffic without needing physical devices. This shift to virtualized network functions makes it easier for companies to quickly adapt to changes, scale their networks up or down, and reduce the need for a lot of specialized equipment.
Although SDN is about managing how data moves through a network, NFV is about running network functions more efficiently through software. When combined with SDN, NFV allows networks to be easily controlled and highly adaptable without needing as much physical hardware.

What Are the Benefits of 5G Network Slicing?

There are many benefits to network slicing, including:

• Flexibility: Offering several types of services simultaneously per slice increases flexibility.
  Customization: Enterprises can tailor workload requirements based on their needs for latency, security, and capacity.
• New revenue: Service providers can realize new revenue because application offerings can increase the ability to use the same physical infrastructure, reducing capex.
  Optimized resource utilization: Dynamic resource allocation allows for sharing, optimizing resource utilization, and reducing OPEX.
• Emerging technologies: Network slicing supports the adoption and deployment of modern technologies without creating new and separate networks.

NETSCOUT 5G solutions offer support for network slicing through proactive monitoring and per slice, providing performance and insights for networks, services, and applications.